Using a photodriven radical-mediated [3 + 2] cyclization reaction to prepare embolic microspheres from sucrose allyl ether without degradative chain transfer

Preparing polymers from allyl monomers without being hindered by degradative chain transfer (DCT) remains a challenge. Herein, we report the synthesis and characterization of embolic microspheres based on allyl monomers for transcatheter arterial embolization using a photodriven radical-mediated [3 + 2] cyclization reaction (PRMC) without metal catalysis. The mechanism of PRMC was validated by thermal and spectral experiments, indicating that PRMC overcomes the restrictions of DCT and makes it possible to synthesize a variety of well-defined polymers from inert allyl monomers. The embolization microspheres based on poly(sucrose allyl ether) were characterized by morphological determination, degradation and swelling tests. Cell experiments show that the microspheres have good biocompatibility. The complete arterial occlusion of the embolized kidneys was observed, indicating that microspheres have broad application prospects in embolization interventional therapy.